Ball-grinding machine.



G. A. HIRTH. BALL GRINDING MACHINE. APPLEEOATION TILED JAN. 27, 1909,

Patented Aug. 23, 1910.

A W m 7 k M a W W C. A. HIRTI-I. BALL GRINDING MAGHINE. APPLICATION FILED JAN.27,1909

, Patented Aug. 23,1910.

3 SHEETS-SEEET s.

//\/ VE/V 70K M nn era-r emf. ALBERT HIRTH, or GANNSIATT, srurrcnnr, GERMANY.

BALL-GRINDING MACHINE.

Patented Aug. 23, 19103.

To all whom it may concern:

Be it known that I, CARL ALBERT HIRTH, a subject of the Emperor of Germany, residing at Cannstatt, Stuttgart, Germany, have invented newand useful Improvements in or Relating to Ball-Grinding Machines, of which the following is a specification.

The invention relates to ball grinding machines, in which one or both of a pair of grinding disks are provided with grooves in which the balls roll, and in which machines the balls, owing to a gap in the track in which they move, are alternatively discharged from and returned to the machine, so that, as the result of continued mixing, the balls are ground in different serial order and in different grooves. This method of workin insures the greatest possible degree of uni ormity in the diameter and superficial character of the balls. According to the present invention it becomes possible to increase the speed of the grinding disks as desired, with the result that not only is the pressure exerted by the disks smaller, though the efficiency is increased, but also the number of balls that can be ground during a -Working shift can be increased, so that a much larger number of balls of uniform size can be turned out per shift than formerly. The accuracy of the grinding has also been improved, because not only are the balls sent forward for fresh treatment more rapidly, but they are only ground to a very small extent during each passage through the machine. The increase in the number of revolutions of the disks is rendered possible in accordance with this invention, by the balls being fed into the tracks between the disks, separately, and with such an accelerated speed that they can enter the machine in very close and uninterrupted serial order. The accelerated speed of the balls vin'entering the machine can be effected, for instance, by feeding the balls into the machine in a row, from a height corresponding with the velocity of the grinding disks, from a track held in a given position and which may consist of a channel or one or more tubes. Another method consists in taking hold of the balls by a rapidly moving device, such as a revolving belt, and, as it were, throwing theminto the machine.

The accompanying drawings illustrate,

accomplishing the desired effect amording to this invention.

Figure 1 is an elevation, partly in section, ofone form of the invention. Fig. 1 is a horizontal section of Fig. 1. Fig. 2 is a View similar to Fig. 1, showing a modification. Fig. 2 is "a plan partly in section. of Fig. 2. Fig. 3 is an elevation partly in section of another modification. Fig. 3* is a plan view of Fig. .3. Fig. 4 is an elevation of another modification. Fig. 4 is a plan thereof. Fig. 5 is a vertical section of another modification taken on line A-A Fig. 6. Fig. 6 is a section on line 13-13 Fig. 5. Fig. 7 is a ver tical section of another modification. Fig. 8 is a front view of the same, viewed from theright hand'side of Fig. 7. Fig. 9 is an elevatlon partly in section of another modification. Fig. 10 is a plan thereof with the upper portion removed.

In Figs. 1 and 2 it is assumed that the grinding disks of the machine are mounted vertically, whereas in Figs. 3 and 4 they are horizontally disposed. The devices in Figs. 5 to 8 are applicable to vertically or horizontally mounted grinding disks. Figs. '9 and 10 show a combination of the devices according to Figs. 2 and 4, the balls being removed from and returned to the ball grinding'machine at different points The balls are ground between the disks a and b, of which, the disk. a, isstationary, while the disk 6, runs loosel on the shaft 0, of the disk (1, and is cause to "rotate by a driven belt pulley d. The balls 6, are received in grooves, which may be provided in one or eachof the grinding disks a, b. In order to remove the balls and re-introduce them d'uringthe working process, the'disk a, is provided with agap f, in which the discharge'cha-nnel g, and the feed channel it, are arranged.

In the modification shown in Figs. 1 and 1, the discharge channel g, is divided above the feed channel k,-into two parts 9 and g, which conduct the balls, removed from the grooves, into a collector 'Z. From the collector'z' the balls are lifted by a device not shown 1n the drawing, mixed together, and passed into the feed channel it. This feed channel 71., consists of separate grooves 72. in which the balls are ranged in a row and are conveyed, at accelerated speed, into the grooves of the grinding disks.

curved channels Z, by .which they are returned to the grooves of the ball grinding machine.

When the grinding disks a and Z), are mounted horizontally, the disk a, containing the gap f, may be arranged either above or below. If it be placed above, it affords, as

-shown in Figs. 3 and 3, the advantage that the feeding of the balls through the feed channel h composed of the groo'ves h}, is facilitated, but, on the other hand, the removal of the balls is rendered more ditiicult. It is efiected-by the balls being lifted out 'ofthe grooves by the gently upward-sloping channels g and pushed up to the highest point of the channels 9 whence they roll down an inclined track and escape from the machine. It is necessarythat the, channels 9 should slope upward, because the balls have to be conducted away over the shoulders of the grooves oi the grinding disk. It the disk a, be underneath (Fig. 4), the removal of the balls from themachine is rendered easier, since as soon as the balls reach the gap 7, they drop out of the machine of their own accord. On the other hand, in this case, the feed channel,.which again is composed-of separate channels 72?, must be bent in order to introduce between the disks (1, b, (from below) the balls descending from above.

In the devices shown in Figs. 5 and 6, the balls are led away and returned through pipes, which can be slitted the whole way along, in order to allow the air to escape as the balls move through them.

The pipes through which the balls are led away, form a downwardly sloping system, crossed by an upwardly sloping system of feed pipes. At the crossing'point, the pipes are bent in pairs in such a manner as to he one above another, with suflicient space between one pair andthe next to allow of the passage of a pair of similarly arranged pipes. of the other system. Thus, the pipes m, of the descending system, bend over the pipes m of the same system, and the pipes 41, of the ascending system over the pipes W, of the same system. I

Fig. 7 is a vertical section through a device by which the balls to be ground retain their serial order as in a-spiral groove, and Fig. 8 is a front view of the same viewed from the right hand side of Fig. 7. The device operates in such a way that the balls 6 which roll in concentric grooves, are taken out of the one groove by the pipes or channels 0, and immediately returned to the adrupted by gaps joining groove, from which after making a single circuit, they are taken out again and fed to the next groove in the same way. From the last groove they pass through a twice bent pipe or channel p into the first groove again. The pipe 79 is provided with branches q and r, through which the balls are fed in succession to the machine, or are removed therefrom, these branches, however, being closed while the machine is running. The branch g is preferably arranged above the innermost groove, into which the- .balls are run in close order when the machine is being filled, until the balls coming into the channel p from the outermost groove, prevent the further admission of balls. In this case the concentricarrangement of the grooves enables a grooved counter disk to be used in place of the plane counter disk of the known ball grinding ma-' chines with spiral grooves, thus aflt'ording the.advantage of a quicker and more 'uniform grinding of the balls.

I Figs. 9 and 10 show a combination of the devices according to Figs. 2 and 4, the balls being removed from and'returned to the ball grinding machine at different points. For

this purpose the stationary disk a is provided with several gaps, instead ofone only, six of these gaps being provided in the example shown. Each gap interrupts one of the tracks traversed by the balls, though several tracks may be adapted to be interrupted by each gap. At the gaps on thestationary disk the balls fall down'auto matically out of the machine, and can be returned, by means of any convenient raising device, to the charging hopper s of the high level feed device, whence they are distributed into separate pipes ,t, which returnthe balls to the machine, through the various gaps in the under disk a. Underneath the charging hopper s a rotary drum u is located, which carries the balls onward and delivers them into the pipes t in close order. Thedrum u is provided with grooves '2; each of which appertains to a pipe .25. By altering the diameter of the drum at each groove 'v the number of balls admitted into the pipes t can be altered in accordance withthe grooves of the ball grinding machine, have to supply a larger number of balls than the pipes issuing into the inner grooves.

What I claim then is 1. A ball grinding machine comprising grinding disks between which the balls are ground, the path of the balls being interthrough which the balls are taken from and re-introduced into the machine, separated means or channels in which the balls to be delivered to the grooves in the disk or disks may run, and means to accelerate the speed of the gravitational feeding travel of theballs between the times semis theyare discharged from and re-introduced into the grooves in the grinding disk or disks so that theballs enter said grooves has close and uninterrupted procession as possible irrespective of the rotatory speed of the diskor disks.

'2. A ball grinding machine comprising grinding disks between which the balls are ground, the path' of the balls being interrupted by gaps through which the balls are taken from and re-intgoghwed into the machine means which form channels for the passage of the balls therealongto the grooves in the grinding disk or disks, and inechanis mconsisting of a revolving device to feed the balls to the feed channels substantially as and for the purpose de Fed.

3. A .ball grinding machine comprising v grinding disks between which the balls are ground, the path of the balls being interrupted by gaps through which the balls are taken from and re-introduced into the machine, means which form channels for the passage of the balls therealong to the grooves in the grinding disk or disks, anda mechanical device consisting oi an endless traveling belt to feed the balls to the feed channels substantially as and for the purpose. described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CARL ALBERT HIRTH.

Witnesses:

IVAN Rmsz, PAUL FUNCIL 

